US Bridges

FM over Tributary Des Moines Riv

FairPosted for load

Boone County, Iowa · 085272704 · Structure no. 000000000078360

Built
1930
95 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
36 ft
1 main span
Daily traffic
71
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Tributary Des Moines Riv is a steel stringer/multi-beam or girder carrying FM over Tributary Des Moines Riv in Boone County, Iowa. It was built in 1930, so it is 95 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 71 vehicles a day, projected to reach 71 by 2044. The structure is 36 ft (11 m) long and 21 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesFM
CrossesTributary Des Moines Riv
Location085272704
RouteCounty Highway 0
CountyBoone County
StateIowa
Coordinates42.14258, -93.97979
Functional classRural Minor Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating25.7 US tons
Inventory rating11.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length36 ft (11 m)
Longest span35 ft (10.7 m)
Deck width21 ft (6.5 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic71 (2022)
Projected traffic71 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Tributary Des Moines Riv built?

It was built in 1930, making it 95 years old in 2025.

What condition is FM over Tributary Des Moines Riv in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in May 2024.

How much traffic does FM over Tributary Des Moines Riv carry?

About 71 vehicles per day (2022 count).

How long is FM over Tributary Des Moines Riv?

The structure is 36 ft (11 m) long with a longest span of 35 ft (10.7 m) and a deck 21 ft wide.

Who owns FM over Tributary Des Moines Riv?

It is owned by the County Highway Agency.